Transcript for:
BWE Lecture: Single Phase Transformer

Hello everyone, yes bacho, kaise ho sab log? Yes, yes, yes, aaj wapas se swagat hai apne BWE ke aakhri chapter ke session number 1 me. Aakhri chapter shuru karne ja raha hu janab because BWE ka bohot sa syllabus maine bilkul detailed me aapko cover kar diya hua hai. I have taught you DC, AC, 3 phase in detail.

Today I am going to start with single phase transformer. I am going to take it in numerical part because theoretical part you can definitely read from textbook. If you have not got textbook then do comment and tell us. We will provide you textbook, best textbook PDF will provide you that too in WhatsApp group.

Ok, let's go. Tell me quickly, can you hear my voice clearly? Is my voice clear? Yes, yes, yes.

Please tell me. Please tell me. Everyone.

Everyone, kids. Yes, yes, yes. Amazing.

Amazing. Let's start. Sir, tomorrow is Sunday. Keep at least 2 hours of session. Sure, Spakji, sure.

I am going to tell you tomorrow's schedule. Don't worry at all. Tomorrow we will take big lectures.

Tomorrow is just for you. Because exams are near. I knew it. In the coming week, you will have exams.

Okay? Let's start with your like. Quickly like, share with all your friends.

Because BWE, there will be a channel on YouTube where all the chapters of BWE have been taken. This is all by the grace of God. Please share this video with your friends and subscribe to our channel.

Okay, let's start with a single-phase transformer. First of all, why is a transformer used? Why is a transformer being used?

Because, to convert AC to DC. To convert AC to DC. Are you getting my point?

To convert one value of AC to another value, a transformer is used in electrical equipment. There are many electrical instruments where we keep looking at this transformer. We can see it here.

It is used in it. Right? So, two coils are most important in a transformer.

two coils without which it is very difficult to make a transformer. It means it cannot be made exactly. So first one is called as a primary coil.

Okay. Primary coils and second one is called as a secondary coil. Okay. Primary coil and secondary coil.

Very important. Without them it can be difficult to make a transformer. Okay.

Secondary coil. It will be fun. Okay. Now, how to do its diagram?

We have already seen the diagram of the transformer in the chapter of electromagnetic induction in 12th standard. Today, I am going to tell you its diagram again. So, pay attention to the diagram.

This is what an one coil, from where my input will go. This is what an core. and this is what and again a secondary coil where I will see output what will be seen output so I will write output here and here I will write input yes input and output ok so obviously from where the input will go that is called primary coil where the output will be given that is called secondary coil are you getting my point primary coil and secondary coil ok now this transformer is in two types Okay, this transformer is available in two types. Yeah, my video and audio are not matching.

Tell me, tell me, tell me. I think it is matching. Chirag ji, I think it is matching. Please check it out. Please check it out once.

Yes, yes, yes, yes, I am moving forward. I am moving forward. Transformers have two types. There are two types.

We can see two types of transformers. Already we have seen that but today I am revising it. Step up transformer.

Step up transformer. Okay, step up transformer. And second one is step down transformer.

What is it? Step down transformer. Step down transformer.

Okay, transformer. It will be fun. Okay, okay, in Chirag Ji, it is fine now, no problem, no problem.

Let's go, step up transformer and step down transformer. What happens here? What happens in step up and step down, sir?

See, primary coil and secondary coil. Here, the coils depend on whether it is a step up transformer or whether it is a step down transformer. Step up, what will it say?

Increase. Increase means number of coils. Increase number of coils. means the number of coils in primary should be less in secondary coil means number of coils in primary is more in secondary coil and number of coils in primary is less then it is called as step up transformer and step down is opposite so it is obvious that number of coils in primary is greater than number of coils in secondary so it is called as step up and step down transformer now I am going according to the paradise law according to the paradise law I am going shell and core type transformer absolutely step up and step down transformer is called sir this shell and core type that is related to the constructive I am talking about related to output ok there are two types related to output shell and core type that is related to construction So, the useful thing for us is step up and step down transformer.

Mostly we use it in practical applications. Okay. So, let me write here. Therefore, according to Faraday's law. According to Faraday's law.

Okay. Faraday's law. What is going to happen? What is going to happen in Faraday's law?

Check it. Faraday's law. E is equal to minus a d phi by dt. That is Lenz's law. Lens law.

Suna bhi raega. Lens law kiske upar depend hai. Faraday iske upar depend hai. Tige.

To apna E is equal to. Main likhun ga minus N1. D5 by DT into V raega. Into V raega.

Okay. Similarly this is for an EMF related to coil 1. Now I am talking about EMF related to coil 2. That is minus of N2 D5 by DT into V. What is n1 and n2? They are number of coils.

What is your phi? That is what your flux and a flux per unit time that is change in flux per unit time that is called as n d phi by dt. Okay. This is this is nothing but a Faraday's law. Why is this minus?

Because sometimes it gets back EMF, reverse EMF, due to which it keeps opposing. It will oppose and due to that opposition, this negative sign will be there. This is what we have studied in Lenslaw.

Now what are the most important theoretical questions to be studied in this? I will tell you the theoretical questions now. First one is the principle of single phase transformer.

This is very important. This question is asked many times in Mumbai University. So, do read it. Principle of Single Phase Transformer.

Second is EMF equation of transformer. EMF equation of transformer. Very good question.

It is a famous question. The three questions that I am going to write are very important. So, please read it carefully. If you don't have a textbook, then tell me in the comment section. Tonight, I will send you the best PDF on WhatsApp.

of PEEE textbook. So, EMF equation and second thing we have to read that is what and transformation ratio. This comes in this only. Transformation ratio. Transformation ratio.

This will come in this only. Transformation ratio. The ratio of 4.44 is very important.

I will write about this. Don't take tension. I am going to tell about the theoretical question first.

Okay. After that I have to read Lawsus and Transformer losses in transformer that TX stands for transformer that is not a transmitter okay that is a transformer so losses in transformer that is ion loss core loss these all losses have to be explained to us copper loss, ion loss, core loss these three losses have to be written to us okay yes provide the pdf after lecture is over I will provide you the pdf Sir, how is Abhijit Chakravarti's book? I will suggest that if you want to read properly from reference book, if you want to learn in detail, then the person whom I am sending the textbook today, the author's name is Ravish Singh and the other is B.R.

Patil. So, you can read from both the textbooks. Both are the best textbooks. There is no mistake in this.

If there is any minor error, then that is also in calculation. Otherwise, theoretical part is best given. Right.

Let's go. Let's go. Okay.

So, let's go. I want to write some formulas here so that you get the benefit of it. Right.

Let's go. Let's go. Let's go. Have everyone reached?

Have everyone reached? Yes. I am going towards EMF equation. Okay. EMF equation of a transformer.

I am giving you all the formulas and will start the numericals. EMF equation of transformer. Transformer.

Okay. EMF equation of transformer. Okay. What is going to be EMF equation?

That is E1 is equal to. Yes. Absolutely. Absolutely.

E. E1 is equal to 4.44 comment is coming yes that is the second number ok good thing start reading it 4.44 F N1 pi M of V this is called as an EMF equation of a transformer and for E2 means EMF at coil 2 means on secondary coil what will be my EMF we will check E1 4.44, 4.44, everything will be same. N1 will come in place of N2. Phi M, V, as it is, as it is.

There will be no difference in it. Are you getting my point? Come on. So far, I think everything is sorted. There should be no problem in this.

I am going to a simple formula here, which is called transformation ratio. Transformation ratio. Okay, very good.

This is a good ratio because it is useful in many numericals. Okay, transformation ratio that is E2 by E1 is equal to N2 by N1. E2 by E1 is equal to N2 by N1 and that is called K and K means transformation ratio.

Okay. We can write this in different ways. I will write it in all ways.

E2 by E1 is equal to N2 by N1 is equal to V2 by V1. Absolutely. V2 by V1 which is equal to I1 by I2. Okay. And this is overall is equal to K.

Means I have written related to potential difference. I have written related to current. I have written related to EMF. And I have written related to number of coils.

Check it carefully. Now for MCQ, the most important thing is that your half exam is going to be in MCQ pattern. So for that I will write one here.

Therefore, for step up transformer, check what will be my transformation ratio for step up transformer. What will be my transformation ratio? So, for step-up transformer, as I said, N2 is greater than N1.

Means, number of coils in the secondary should be greater than the number of coils in the primary. Okay. So, here the transformation ratio, K, will be greater than 1. It is a natural thing. There is no need to make a mistake. Here, if N2 is greater than N1, then obviously, K's value is going to be greater than 1. Okay.

Let's go. Let's go. Let's go. Absolutely.

Tushar ji, I was in 12th standard. It is my duty to revise. Otherwise, everything will go by the wayside. So, for all these things, I am revising everything. I have already said that I was in 12th standard in EMI.

Right? Absolutely. Absolutely.

Come on. Done. Done. Write it down. Do write it down.

It will help you. It is useful for you in future. Right?

Let's go. Next one, as I said, transformer losses, this is not in 12th, transformer losses, different losses will be of transformer, what losses are going to be, 1 by 1, 1 by 1, we will write, first one, primary, primary, copper, loss okay primary copper loss. So, see copper both the coils will remain copper. So, primary copper loss means for primary coil.

Secondary copper loss means for secondary coil. Okay. So, primary copper loss is going to be I1 square R1 into W.

Okay. I1 square into R1 into W. W is nothing but windings. Windings is going to be there.

Obviously, this is given to me in question. Okay. Next one. Secondary secondary copper loss secondary copper loss check what is going to be i2 square r2w ok any doubt now I have to see total copper loss of both of them therefore total copper loss total copper loss see there is an introduction session today so obviously I am not going to take tomorrow as I promised it is Sunday I will tell you the timings. We will take 4 sessions.

If you want to take one hour, then we will try to cover your whole syllabus tomorrow. I will finish most of the syllabus tomorrow. Don't worry. Okay. And the paper discussion, how to write the university paper, what to write, for that, the candid talks session is arranged tomorrow.

I will tell you the details of that at the end of the lecture. Okay. let's see what will happen total copper loss see what is in it W will be taken out of the common rest of the things will be kept as it is ok addition is to be done obviously total is not there so obviously what will I have to do addition will have to be done this is called as a total copper loss check check what has happened to everyone till here this is called this is called WCU ok let's go I am going to tell you about the iron loss in the next video. Don't worry. Write it down.

I will give you the formula of impedance. What all will happen in impedance? We will check it. impedance me CD bath Z1 is equal to under root of yaha perrega R1 square plus X1 cos square obviously impedance at the wall may raga amlogini already AC may be high three phase may be high right G okay next one next one Z2 is equal to under root of R2 square plus X2 cos square or yaha per welcome me he will raga okay I will tell you all the details in the next part.

Don't worry. I will start the numerical part from the next time. For now, you have to read all these formulas in detail. I have given all the formulas deliberately.

Today, you start reading the theory. I will send you the pdf of the textbook in the group. Whether you are from group number 1 or whether you are from group number 2. In both the groups, you have written BEE.

PDF of BWK textbook you will get it now. Ok, so what are the scenarios for tomorrow? I am going to tell you today. Tomorrow is the weekend, tomorrow is Sunday.

Ok, what will happen tomorrow on Sunday? First time, first time very important, there will be a session at 10 am. After that, there will be a session at 1 pm. Then there will be a session at 4 pm. 7 o'clock, we will be doing these four sessions tomorrow.

Okay, we will be doing the 10 o'clock session there. Absolutely successive, successive differentiation's one-shot revision. Differentiation's one-shot revision. We will be finishing the entire chapter in an hour. Everyone should not worry about it.

So tomorrow there will be a one shot revision of successive differentiation. Okay. Next one.

Next one 1 pm. Bindu Sharma ji, application of partial differential is already done. Homogeneous functions, go and see.

Homogeneous functions, go to the videos section of your channel. And there you will get all the homogeneous videos. Okay. We will be doing it at 1 o'clock tomorrow.

We will be doing it at 1 o'clock tomorrow. Okay, doubt of partial differentiation. Bindu Sharma ji, Nilesh ji is saying, Nilesh ji I will give you the reply today, don't worry.

At 1 o'clock we will be doing the chapter of Transformer. We will be doing the session number 2 of Transformer. We will be doing numericals tomorrow.

At 4 o'clock, how to appear. for university exam university exam tomorrow I will tell you the whole strategy on which day what exam to appear how to tackle MCQs how to write the subject part to pass first of all I have to focus on whom you will get all this in tomorrow's 4 o'clock session ok next one obviously you will get everyone's link on your group so don't worry about it ok next next tomorrow we will be doing DC circuit 7 o'clock DC circuit remaining session no 2 DC circuit one short revision tomorrow we will be doing already one revision session i took last time its continuation will be tomorrow 7 o'clock and if possible then 10 o'clock night session i will tell you 10 o'clock we will be doing a session of math, we will move forward with the expansion of functions. So, you have to attend these four or five sessions completely compulsory.

Because this is absolutely free, all these videos are going to be public, but what is the benefit of live? You can directly ask me doubts and I can solve your doubts at that time. So let's move forward. Okay, thank you so much Bindu Sharma ji.

Thank you so much. So, we will meet in tomorrow's four sessions. Till then, bye-bye. Take care of yourself and thank you so much guys.